It is known that common spin-on oil and fuel filters used on all diesel and petrol engines result in accumulated moisture and particulate contamination. This depletes the engine oil additive package, including Total Base Number (TBN), resulting in undesirable sludge, varnish and accelerated oil oxidation. Also, fuel economy and emission standards prematurely deteriorate as the Original Equipment Manufacturers (OEM) design function of the fuel injection systems and piston rings become impaired. Hence, the engine oil is ‘spent’ at only 250-500 hours in a diesel engine and 10,000 miles in a car petrol engine.
The primary issue with common spin-on oil filters is that they are full flow (70-185 litres per minute depending on the size of the engine) at approximately 80 psi. They only start filtering particulate at 30 to 40 μm and have no capacity to absorb or retain moisture. The technical issue with spin-on oil and fuel filters not retaining moisture in emulsion is that ‘the presence of wear metals alone can cause oxidation rates to increase to five (5) times the normal rate, while the presence of water can increase the oxidation rate ten (10) times. Combined, water and metal catalysts can increase the oxidation rate fifty (50) times or more’ (ref: USA National Tribology). From this, one learns that it is moisture contamination that accelerates oil oxidation ×10 and this critical issue was either not known, or was ignored in 1950's designed common spin-on oil and fuel filters that are still used today in all engines.
Another type of filtering device is known as edge-on or depth filtration, used in bypass kidney loop oil filtration. These are known to be most effective, but are mainly sold in the aftermarket, where there is consumer resistance to fitting hose connections and unwarranted concerns about engine warranty.
The present invention attempts to overcome at least in part some of the aforementioned disadvantages of previous filtering devices.